IWS Info

Intermittent Water Supply IWS

A new LEAKSSuite Info-Hub on taking back Control

In a recent article for the IWA’s The Source magazine, Bambos Charalambous, the Chair of the IWA Water Loss Specialist Group’s Intermittent Supply Working Group, highlighted the close link between intermittent supply and water loss. Pressure flux compromises the network’s structural integrity. Pipe and service connection failures increase. Meters malfunction. Illegal connections spread. The network deteriorates to the point where it is next to impossible to detect and fix leaks, and water contamination leads to poorer water quality and increases risk of water-borne illness, creating public health issues. Customers become less satisfied with their water service, their willingness to pay tariffs (and utility revenues) decline as the utility struggles to conduct maintenance and improve service with lower financial resources. Understanding the negative feedback loop is important ‘It is relatively easy to turn a 24/7 system to an intermittent supply,” says Charalambous, ‘but it is very hard to do the opposite.’

Intermittent supply also seriously compromises the use of many of the practical concepts that have been developed for management of NRW and its components in continuous supply systems. At a recent Masterclass, a number of international experts with wide experience of intermittent supply in different countries discussed the topic in detail over 4 days, and agreed to contribute papers and other relevant material to a new IWS Info-Hub on the LEAKSSuite website. Priority will be given to papers, presentations and articles which stress the importance, and the benefits, of trying to move from intermittent to continuous supply, even at low pressure; and choice of the most appropriate sequences of activities, and the most relevant performance indicators to use for setting targets and assessing progress.  

In accordance with LEAKSSuite’s philosophy that papers and presentations should be free to all, authors who have not previously assigned copyright of their material have agreed that any of the material in the Info-Hub can be downloaded free of charge; our only request is that the source is acknowledged if any part of the material is reproduced elsewhere. Papers that are available free under Open Access arrangements from other websites will also be listed. Papers and publications which can only be purchased from elsewhere are listed in the Bibliography.

We hope the easily accessible information on this website will encourage Utilities with IWS to move towards, and eventually achieve, the objective of continuous supply.

We are commencing this initiative with a keynote paper by Bambos Charalambous on the medium to long term effect of intermittent supply during severe drought on a distribution system which was previously continuously supplied and had achieved a good leakage management performance. It provides a warning to those who may consider that moving to rota cuts is a simple short-term response to drought management, with few adverse consequences. 

Additional papers and presentations will be added in coming months as permissions (by authors and Open Source publication) to list them on the LEAKSSuite website are received. 

Table updated Sep 1st 2017

Monterde, NChallenges in moving to 24/7 water supply in Aguas de Saltillo City, Mexico Presentation IWS 2017G
Simukonda K, Farmani R, Butler D Causes of water supply intermittency in Lusaka City in Zambia.Presentation IWS 2017F
Charalambous BINTERMITTENT WATER SUPPLY: Ten Reasons why it should be Avoided Presentation IWS 2017D
Peña M, Bazet J.I, Poona V.A.Pressure Management and System Stabilisation: Case Study in eSikhaleni, South AfricaPresentation IWS 2017B
Charalambous B,The Effect of Intermittent Supply on Water Distribution NetworksPaper IWS 2016Z
Charalambous B, Liemberger R,Dealing with the complex Interrelation of Intermittent Supply and Water Losses. Paper and Presentation at IWA World Congress, Brisbane, Australia, October 2016Paper IWS 2016R
Presentation IWS 2016S